Unfortunately there are examples of vessels drifting aground with either one or two anchors secured in the hawse pipe. There is rarely any excuse for this.
Below we have listed a few key points for the Master’s consideration, assuming that the vessel is drifting towards shoals, and is unable to make way with neither main engines or thrusters. Needless to say, proper maintenance of the ground tackle can prove to be vital in such a situation.
The Master should consider the following the in case of emergency anchorage:
- It is preferable to deploy the starboard anchor first, as the chain is longer. But the threat of the situation should not be underestimated, and the Master should consider going ”all the way” and deploy both anchors. Nothing should be left untried.
- Consider ocean bottom topography, and check the chart for underwater pipelines and other obstructions. Search for the best holding ground along the course the ship is drifting.
- It is not wise to let out the entire chain early and hope that the anchor will fasten when the depth decreases. This should only be done when it is very deep all the way, or close to the shoreline, as the anchor may be damaged using this approach. Another pitfall with this method is that you might lose the anchor due to difficulties when braking.
- It might be wise to use the windlass under power to veer out the anchor in a controlled manner, if auxiliary power is available and there is enough time, if auxiliary power is available and there is enough time. But bear in mind that if the wave height causes the vessel to pitch, the anchor may be damaged if it hooks fast upon hitting the bottom. Take into consideration whether the bottom conditions are rocky or uneven.
- The cable length-to-depth ratio should be as large as possible. A ratio of 5 to 1 is very good, but bear in mind that the ship should not get too close to shore.
- Avoid heaping the cable at the bottom.
- Also deploy the port anchor, as this will provide a more balanced holding power. Deploy the port anchor after having veered 2–3 shackles on the starboard anchor. Then carefully veer maximum cable on both anchors.